The correct spelling for this word is coterminous. The meaning of coterminous is to have the same coincidental boundries as another person or to coexist in one scope.
The states of Texas and Arkansas are coterminous
The two properties have coterminous boundaries, meaning they share a common border.
This situation is conterminous
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Both coterminus and coterminous are used, only the -ous is included in most sources. "COTERMINUS" (listed as a business variant) : two or more linked business contracts, set to expire at the same time. COTERMINOUS (accepted spelling): having the same coverage, range, or scope (coterminal, coextensive)
George A Hufford has written: 'FM broadcast coverage of the coterminous United States' -- subject(s): FM broadcasting
Most of the high-density areas are coterminous with the alluvial plains on which intensive agriculture is centred.
Both terms are used, only the -ous is included in most sources. "COTERMINUS" (listed as a business variant) : two or more linked business contracts, set to expire at the same time. COTERMINOUS (accepted spellings): having the same coverage, range, or scope (coextensive) COTERMINAL : having a common end point (as in geometric angles) CONTERMINOUS : having a common end or boundary
Vivian Barry has written: 'New York City's coterminous service districting plan' -- subject(s): Municipal services, Neighborhood government
(adj.) Linked, as two or more agreements or contracts (such as leases), so that both expire or terminate at the same time.Note the confusion caused by the similarity of the -usending (a case marker, here, the nominative ending of the second-declension Latin noun terminus) to -ous (an adjectival ending). "Coterminous" is (correctly) an adjective, meaning "having the same boundaries; of the same duration." "Coterminus" is more correctly a noun, meaning perhaps the shared beginning or ending point (the terminus) of something that is "coterminous."The use of "coterminus" as an adjective is arguably incorrect.
Montgomery, Bucks and Delaware Counties in Pennsylvania and Burlington., Camden and Gloucester Counties in New Jersey.